Routers are electrical devices that are used to permit computers and networks of computers to pass data back and forth. A router typically has one or more input ports and one or more output ports. Data packets containing a destination address arrive on an input port. Based on the destination address, the router forwards the data packet to an appropriate output port which may be connected to the destination computer system or to another router. The data being transmitted between routers may be confidential (e.g., bank account data in the context of a bank's network) and thus the security of such data should be ensured. Accordingly, at least some routers provide encryption to allow secure communications across an untrusted communication channel, such as the Internet.
Additionally, some such routers provide additional security to protect the configuration of the routers themselves, but such configuration protection measures sometimes operate on the presumption that a person or group of persons authorized to configure the router is/are authorized to control all data traffic through the router. Thus, for security reasons such a router may only be used to route data to or from a limited number of destinations and sources that are all under the control of the authorized person or group. If additional data to or from other destinations and sources controlled by others is needed, additional routers must be added to such a network, thereby incurring a corresponding increase in installation and maintenance costs, as well as complexity.